Which image file format is not recommended for web use due to its large size?

TIFF, or Tagged Image File Format, is not recommended for web use mainly due to its large file sizes, which can significantly impact website load times and overall performance. TIFF is designed for high-quality images and is often used in professional photography and printing where image fidelity is paramount. Because it supports various color spaces and can store images with high bit depths, TIFF files tend to be much larger than other formats, making them unsuitable for the web, where quick loading times and efficient file sizes are essential for a good user experience.

In contrast, formats like JPEG, PNG, and GIF are more optimized for web use. JPEG is widely used for photographs due to its ability to compress images without overly compromising quality, while PNG is favored for images requiring transparency or a higher color depth, even if it generally creates larger files than JPEG. GIF is mainly used for simple graphics and animations, and although its file sizes can also be larger compared to bare-bones formats, it still remains manageable for web applications.

Thus, of all the options, TIFF's significant file size makes it ill-suited for efficient web use, reinforcing the rationale behind choosing this format as the correct answer.